Through a longitudinal study of approximately 6000 coke-oven workers we will characterize the histopathology of lung cancer occurring in this high-risk occupation and determine if repeated sputum cytology studies reveal a sequence of changes leading to lung cancer. We seek also to determine if coke workers who develop lung and other cancer have elevated levels of tumor markers such as serum CEA, serum and urine polyamines. We will try to ascertain if the presence of tetraploidy characterizes cells in lung cancer. Factors influencing these changes will be examined, especially cigarette smoking history, job location and duration. This information will be used to propose cancer control strategies for this group of workers.